866971 has 4 divisors (see below), whose sum is σ = 990832. Its totient is φ = 743112.

The previous prime is 866969. The next prime is 867001. The reversal of 866971 is 179668.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 866971 - 2¹ = 866969 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 866971.

It is not an unprimeable number, because it can be changed into a prime (866941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61920 + ... + 61933.

It is an arithmetic number, because the mean of its divisors is an integer number (247708).

2⁸⁶⁶⁹⁷¹ is an apocalyptic number.

866971 is a deficient number, since it is larger than the sum of its proper divisors (123861).

866971 is a wasteful number, since it uses less digits than its factorization.

866971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123860.

The product of its digits is 18144, while the sum is 37.

The square root of 866971 is about 931.1127751245. The cubic root of 866971 is about 95.3531087909.

Adding to 866971 its product of digits (18144), we get a triangular number (885115 = T₁₃₃₀).

The spelling of 866971 in words is "eight hundred sixty-six thousand, nine hundred seventy-one".